<< Chapter < Page Chapter >> Page >
This module is part of a collection of modules for a class project on matrix completion techniques for the sensor network localization problem done for the Fall, 2009 offering of Prof. Baraniuk's ELEC 301 course at Rice University.

Results, conclusions, and future work

Random knock-out trials

The results from the simulations for the random knock-out runs are displayed in the figures below, which depict the average relative Frobenius-norm error over 25 trials versus fraction of unknown entries.

Simulation results for random knock-out trials with no noise.
Simulation results for random knock-out trials with noise present.

As these two figures illustrate, the results for the random knock-out trials were quite good. As expected, as the fraction of unknown entries becomes large, the error eventually becomes severe, while for very low fractions of unknown entries, the error is extremely small. What is amazing is that for moderate fractions of unknown entries the algorithm still performs remarkably well, and its performance doesn't degrade much by the loss of a few more entries:the graphs are nearly flat over the range from 0.3 to 0.8! As the second figure shows (and as might be imagined), noise only makes the error worse; however, the plot also shows that the algorithm is reasonably robust to noise in that perturbations of the distance data by small amounts of noise don't become magnified into massive errors.

As an example, consider Figure 3 below, which displays the results of a typical no-noise random knock-out run with knock-out probability 0.5. On the left is a plot of the sparsity pattern for the incomplete matrix. A blue dot represents a known entry, while a blank space represents an unknown one. On the right is a plot of what the network looks like after being reconstructed using multidimensional scaling. Observe that the red circles for the networkcorresponding to the network generated by the completed matrix enclose the blue dots of the original network's structure quite well, indicating that the match is very good.

Results from a typical no-noise random knock-out trial with a knock-out probability of 0.5. Left: Sparsity pattern for the incomplete matrix. Right: Overlay figure demonstrating degree of agreement between the original network and the network generated from the completed matrix.

For an illustration of how the results look with noise, see Figure 4 below. This figure shows the results of a typical noise-present random knock-out run with knock-out probability of 0.5 and noise standard deviation 0.05. The agreement in the reconstructed network is not as good as it was for the no-noise case, but the points of the reconstructed network are “clustered" in the right locations, and some of the prominent features of the original networkare present in the reconstructed one as well.

Results from a typical noise-present random knock-out trial with a knock-out probability of 0.5 and a noise standard deviation of 0.05. Left: Sparsity pattern for the incomplete matrix. Right: Overlay figure demonstrating degree of agreementbetween the original network and the network generated from the completed matrix.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get the best Algebra and trigonometry course in your pocket!

Source:  OpenStax, A matrix completion approach to sensor network localization. OpenStax CNX. Dec 17, 2009 Download for free at http://cnx.org/content/col11147/1.1
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'A matrix completion approach to sensor network localization' conversation and receive update notifications?